/**
 * File extension utilities that handle edge cases:
 * - Hidden files (e.g. `.gitignore`) are not treated as having extensions.
 * - Filenames with trailing dots (e.g. `file.`) preserve the trailing dot as an extension.
 * - Filenames that are only a dot or have no extension return empty string or undefined appropriately.
 */
/**
 * Extracts the file extension including the leading dot.
 *
 * Handles:
 * - `.hiddenfile` -> `''`
 * - `file.txt` -> `.txt`
 * - `file.` -> `.`
 * - `file` -> `''`
 * - `.` -> `''`
 *
 * @param {string} filename - The filename to parse.
 * @returns {string} The extension (including dot) or empty string if none.
 */
export declare function getExtension(filename: string): string;
/**
 * Extracts the extension name (without the dot) from a filename.
 *
 * Handles:
 * - `.hiddenfile` -> `undefined`
 * - `file.txt` -> `txt`
 * - `file.` -> `''`
 * - `file` -> `undefined`
 *
 * @param {string} filename - The filename to extract from.
 * @returns {string | undefined} Extension name or undefined if none.
 */
export declare function getExtensionName(filename: string): string | undefined;
/**
 * Removes the file extension (including the dot) from the end of a filename.
 *
 * Handles:
 * - `file.txt` -> `file`
 * - `file.` -> `file`
 * - `.hiddenfile` -> `.hiddenfile`
 * - `file` -> `file`
 * - `.` -> `''`
 *
 * @param {string} filename - The filename to modify.
 * @returns {string} Filename without the extension.
 */
export declare function removeExtension(filename: string): string;